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Discussion Starter #1 (Edited)
Hey guys, I've been wanting to test out the velocity and accuracy differences with the LEE FCD and I've finally had the chance to test it out. What I did was I loaded up 30 rounds of the Sierra 90 Gr. HP with 32.5 Gr. of X-Terminator powder with no cannelure and no Crimp. I then loaded up 30 more rounds with no cannelures but a 1/2 turn crimp, and I loaded up 30 more rounds with cannelures and a 1/2 turn crimp.

Here are some details before I begin:
Sierra 90 Gr. HP:

Bullet: .277 Sierra 90 Gr. HP.
Brass: SSA.
Primer: CCI #41.
OAL: 2.260".
Gun: Ko-Tonics 20" Chrome Lined 1:11" twist.
Optic: Swarovski Z6i 1x6 scope set on 6x.
Target Range: 2 10 round shot goups @ 100 yards.
Chrony Distance: (@5')
Temp: 50.

1. No Cannelures and No Crimp:
Shot Group #1: .995"
Shot Group #2: 1.062"
Shot Group Average: 1.0285"
Velocity: 32.5 Gr. of X-Terminator: Avg: 2878fps, Lo: 2861fps, Hi: 2904fps, ES: 43, SD: 14
Picture of Shot Group:


2. 1/2 turn Crimp and No Cannelures:
Shot Group #1: .827"
Shot Group #2: .968"
Shot Group Average: .8975"
Velocity: 32.5 Gr. of X-Terminator: Avg: 2887fps, Lo: 2861fps, Hi: 2904fps, ES: 43, SD: 12
Picture of Shot Group:


3. 1/2 turn Crimp and Cannelures:
Shot Group #1: 1.185"
Shot Group #2: 1.209"
Shot Group Average: 1.197"
Velocity: 32.5 Gr. of X-Terminator: Avg: 2888fps, Lo: 2873fps, Hi: 2898fps, ES: 25, SD: 10
Picture of Shot Group:


Velocity Differences:
As far as velocity goes, I got a velocity of 2887fps and 2888fps with the crimped bullets and a velocity of 2878fps without a crimp. I used 10 round shots to test the velocity. From the results I got an increase in 10fps so I guess there is some truth that using the LEE FCD will give you an increase in velocity, although very minimal.

Accuracy Differences:
From the results I got, there was very little difference in the bullets with a crimp and the bullets with no crimp, which is a good thing and shows that the Crimp did not reduce accuracy, and it actually was a hair bit better. Now, the bullets wiith the cannelures and a 1/2 turn crimp were not as accurate, but I don't know if that was because I was getting tired since I did shoot approximately 100 rounds prior to starting the testing. I will go back on Tuesday and try some more accuracy testing to see if there is a difference with cannelures and no cannelures.

Conclusion:
I'm very happy that the LEE FCD did not hurt the accuracy in any way and the extra 10fps is just a little bonus.

On a side note: I was very happy that I was able to get sub MOA 10 round shot groups at 100 yards with a chrome lined barrel and a 6x scope, especially since I used X-Terminator Powder, which is the cheapest powder available for the 6.8SPC. It even beat the Reloaders 7 in the accuracy department today.

To be Continued...
 

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Good work, Paulo. Vindicates what we've been saying, eh? I just picked up some 90gr HP's (both speer and Sierra) and was wondering what your favorite powder is for that weight? The three I'm looking at is RE7, H4198, and the X-terminator. Just wondering since you've done so much work on these bullets.
 

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Discussion Starter #3
rcrandall said:
Good work, Paulo. Vindicates what we've been saying, eh? I just picked up some 90gr HP's (both speer and Sierra) and was wondering what your favorite powder is for that weight? The three I'm looking at is RE7, H4198, and the X-terminator. Just wondering since you've done so much work on these bullets.
Thanks Bro. For the 90 Gr. bullets use the Reloaders 7, X-Terminator, H335, and even TAC. I wouldn't waste my time with H4198. H322 is also pretty good. I like loading both bullets at 2.260"

Max for the X-Terminator is 32.5 Gr.
Max for the Reloaders 7 is 28.6 Gr.
Max for the H335 is 33 Gr.
Max for the TAC is 33.5 Gr.
Max for H322 is: approximately 31.5 Gr. (H322 is a little too slow for the 90 Gr. bullets. They are compressed with 31 Gr. of H322 and only produce 49000psi).
 

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paulosantos said:
Max for the X-Terminator is 32.5 Gr.
Max for the Reloaders 7 is 28.6 Gr.
Max for the H335 is 33 Gr.
Max for the TAC is 33.5 Gr.
Max for H322 is: approximately 31.5 Gr. (H322 is a little too slow for the 90 Gr. bullets. They are compressed with 31 Gr. of H322 and only produce 49000psi).
Are these the max loads you used before you had pressure issue, or the max for good accuracy in your barrel, or the max just for this test? I remember you getting almost 100 FPS more velocity out of the 90's in earlier tests? I fact I remember higher numbers than this from your 16" . Am I missing something?

Tim
 

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Discussion Starter #6
Tim_W said:
paulosantos said:
Max for the X-Terminator is 32.5 Gr.
Max for the Reloaders 7 is 28.6 Gr.
Max for the H335 is 33 Gr.
Max for the TAC is 33.5 Gr.
Max for H322 is: approximately 31.5 Gr. (H322 is a little too slow for the 90 Gr. bullets. They are compressed with 31 Gr. of H322 and only produce 49000psi).
Are these the max loads you used before you had pressure issue, or the max for good accuracy in your barrel, or the max just for this test? I remember you getting almost 100 FPS more velocity out of the 90's in earlier tests? I fact I remember higher numbers than this from your 16" . Am I missing something?

Tim
Those are the recommended max from the powder companies and that is what I go by and I don't go too far above those numbers.

I got 100 fps more with the H4198 powder:

Speer 90 Gr. TNT with 28.6 Gr of H4198:
16" Barrel: 2854 fps Average.
20" Barrel: 2984 fps Average.
Difference: 130 fps.

With the other powders I'm getting around 2880-2900fps from my 20" barrel and around 2800fps from my 16" barrel.

If you want velocity with the 90 Gr. barrels use H4198 or Reloaders 7.
 

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Discussion Starter #9
rcrandall said:
Why did you steer me away from H4198? Accuracy? I know RE7 is very fast powder, how does it perform concerning cycling the bolt carrier group?
I got away from the H4198 because of the cycling issues. The accuracy of the H4198 was pretty good but not as good as the H322 in my 16" barrel. RE7 cycles fine and is almost as fast as the H4198 and accuracy is a little better than H4198 for me. The problem with H4198 and RE7 is that they are best used with the 90 Gr. bullets and only decent with the other bullets.

I wanted a powder that would work with 90-135 Gr. bullets and that is why I went with the X-Terminator Powder. To my surprise, my barrel really likes X and it is also cheap.
 

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Paul, Looks like your groups are getting better, are you doing anything different?

I read an article, these two guys wanted to know why factory ammo wasn't more accurate. They pulled the bullets saved the powder and only trimmed the brass to a consistent length, deburred the flash hole and uniformed the primer pockets. Then they reassembled everything and the groups went from over 1 inch to around 5/8 with 1 group being .4".

Benchrest guys from 6mmBR.com

Did you decide on a new trigger?
 

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Discussion Starter #11
constructor said:
Paul, Looks like your groups are getting better, are you doing anything different?

I read an article, these two guys wanted to know why factory ammo wasn't more accurate. They pulled the bullets saved the powder and only trimmed the brass to a consistent length, deburred the flash hole and uniformed the primer pockets. Then they reassembled everything and the groups went from over 1 inch to around 5/8 with 1 group being .4".

Benchrest guys from 6mmBR.com

Did you decide on a new trigger?
I am using the WOA Tuned RRA 2-stage trigger now and that has helped a lot. I loaded up some more ammo for Tuesday and I placed cannelures on the bullets but I didn't go as deed this time with the cannelures. Hopefully that will help out. I also wish I had a more powerful scope for shooting. Something around 20x would be nice.
 

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What scope are you using now? Magnification?

I have a Leupold VX-III Long-range Tactical 4.5-14 power with a 40MM objective. At 100 you can literally line up the cross hair on the lines of the target. With my Sako TRG-22 I have been able to shoot sub .25 moa 5 shot groups with that scope. The bullet hole isn't covered by the cross hairs so I think that may help as they are nothing more than a one hole group. But I am going to be getting rid of both which really hurts.

Tim
 

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Discussion Starter #13
Tim_W said:
What scope are you using now? Magnification?

I have a Leupold VX-III Long-range Tactical 4.5-14 power with a 40MM objective. At 100 you can literally line up the cross hair on the lines of the target. With my Sako TRG-22 I have been able to shoot sub .25 moa 5 shot groups with that scope. The bullet hole isn't covered by the cross hairs so I think that may help as they are nothing more than a one hole group. But I am going to be getting rid of both which really hurts.

Tim
Swarovski Z61 1x6 scope. I was using an IOR 2.5x10-42, but I had to sell it to get the Swarovski. I love the Swarovski, but for shooting groups, a little more magnification would help.

http://68forums.com/viewtopic.php?t=680
 

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Discussion Starter #15
I went out again today and shot some more with the crimped bullets with cannelures and accuracy was a little better. This time, when I rolled the cannelures with the Corbin Cannelure Tool, I didn't go as deep and that seemed to help with the accuracy.
 

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Based on what you have found I think the cants definitely effect accuracy. You may be able to find a happy medium between how deep they are and not having them at all, but for the utmost in accuracy I think you have to go with no cannelure. I don't know if there is any tech deference between your tool done ones and the factory ones. I guess shooting the SMk with and without for groups would show this. I do find it interesting that the crimped only ones seem to show better accuracy. I would think you may actually get more velocity because of the increase in initial pressure from the friction cause by the crimp.

Tim
 

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What I have found when using the LFC die, in all calibers I load for and that is about a dozen plus rifle calibers, is that when using bullets with no crimp groove, no crimp is good, 1/4 crimp is great, and 1/2 turn crimp blows things to hell. When using factory crimp grooved bullets going to 1/2 turn crimp gives the best accuracy in my rifles and handguns.
I use the CH-4D crimp cutting tool on some handgun and rifle loads and have found that if you cut too deeply it will ruin accuracy. The only bullet I have found that cutting a deep groove did not hurt accuracy is when cutting a groove in a solid copper X bullet. All lead core bullets I have put crimp grooves in had to be done very shallow or the concentricity is ruined and groups go to hell in a hand basket.
 

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Big Bore, for people that don't have or aren't sure could you give a brief description of what or how a 1/4 ,1/2, or full crimp is achieved.


Thanks

Tim
 

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Discussion Starter #19
Tim_W said:
Big Bore, for people that don't have or aren't sure could you give a brief description of what or how a 1/4 ,1/2, or full crimp is achieved.


Thanks

Tim
Big Bore is referring to 1/2 Turn or 1/4 Turn of the Lee FCD Die. When setting up the Lee FCD Die, you just have to raise the shell plate up and screw the Lee FCD Die down until it touches the plate. Then you turn it 1/2 turn and you are ready to go.

In his case he turns the Lee FCD die 1/4 turn for bullets without cannelures and 1/2 turn for bullets with cannelures.
 
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